The Mustard Seed
Another parable put he forth unto them, saying, The kingdom of heaven is like to a grain of mustard seed, which a man took, and sowed in his field: Which indeed is the least of all seeds: but when it is grown, it is the greatest among herbs, and becometh a tree, so that the birds of the air come and lodge in the branches thereof.
Matthew 13:31-32
When faith begins, it begins as a seed. A seed sown, the name of Jesus, and faith comes into the heart. A man believes unto salvation, and a new thing is born.
When faith grows, it begins its work, even as a yeast within a dough, or fermentation within a wine. It does its work secretly, silently, producing changes through the whole.